Which adverse effect is associated with amiodarone therapy?

• A. Pulmonary fibrosis
• B. Hypertension
• C. Hyperkalemia
• D. Hypernatremia

Answer: (A)

When a medication causes serious lung toxicity, one of the classic and most feared effects is pulmonary fibrosis from amiodarone. Amiodarone is highly lipophilic and tends to accumulate in tissues, including the lungs, where it can provoke a chronic inflammatory reaction that leads to interstitial pneumonitis and, with time, fibrosis. This risk increases with longer use, higher cumulative doses, older age, and preexisting lung disease.

Clinically, patients may develop a gradual onset of shortness of breath, dry cough, and fatigue. Imaging often shows interstitial or ground-glass changes, and lung function tests reveal a restrictive pattern with reduced diffusion capacity. The key management step is stopping the drug and, in more significant cases, initiating corticosteroids to quell the inflammatory process. Because amiodarone lingers in the body for a long time, monitoring and follow-up are crucial, even after discontinuation.

Hypertension is not a typical or primary adverse effect of amiodarone; it can cause other issues like bradycardia or hypotension, especially with IV use, but not a diastolic rise in blood pressure. Hyperkalemia and hypernatremia are not characteristic adverse effects of amiodarone either, so they don’t fit the pattern of its well-known toxicities. The pulmonary fibrosis risk stands out as the most established and clinically important adverse effect associated with amiodarone therapy.